scholarly journals P.002 Neurodevelopment at 2 years in asphyxiated newborns treated with hypothermia can be predicted by early neuroimaging markers

Author(s):  
FJ Al Amrani ◽  
P Wintermark

Background: Brain imaging in asphyxiated newborns treated with hypothermia has shown that brain injury can be identified as early as day 2 of life and continue to evolve over the first month of life. Methods: Asphyxiated newborns treated with hypothermia were enrolled prospectively. Apparent diffusion coefficient (ADC) and fractional anisotropy (FA) were measured on magnetic resonance imaging (MRI) performed over the first month of life. Neurodevelopment was evaluated around 2 years of age. Results: Twenty-six asphyxiated newborns treated with hypothermia were enrolled. In asphyxiated newborns treated with hypothermia, who developed cerebral palsy, ADC values were significantly decreased on day 1 of life, on day 2-3 and around day 10 of life in the thalamus. In the same newborns, the FA values were significantly decreased on day 10 of life. Conclusions: Early MRI measurements permitted to identify the newborns developing cerebral palsy as early as on day 1 of life and could thus be used in the future to predict the long-term neurodevelopmental outcome asphyxiated newborns treated with hypothermia.

2017 ◽  
Vol 08 (02) ◽  
pp. 185-193 ◽  
Author(s):  
Pramod Kumar Gupta ◽  
Rishi Awasthi ◽  
Shalini Singh ◽  
Sanjay Behari ◽  
K. J. Maria Das ◽  
...  

ABSTRACT Purpose: Studies have shown that cellularity of glial tumors are inversely correlated to minimum apparent diffusion coefficient (ADC) values derived on diffusion-weighted imaging (DWI). The purpose of this prospective exploratory study was to evaluate whether temporal change in “minimum ADC” values during follow-up predict progressive disease in glial tumors post radiotherapy and surgery. Materials and Methods: Adult patients of glial tumors, subjected to surgery followed by Radiotherapy (RT), were included in the study. Serial conventional magnetic resonance imaging with DWI at the following time points – presurgery, pre-RT, post-RT imaging at 3, 7, and 15 months were done. For “minimum ADC” values, multiple regions of interest (ROI) were identified on ADC maps derived from DWI. A mean of 5 minimum ADC values was chosen as “minimum ADC” value. The correlation was drawn between histology and minimum ADC values and time trends were studied. Results: Fourteen patients were included in this study. Histologies were low-grade glioma (LGG) - 5, anaplastic oligodendroglioma (ODG) -5, and glioblastoma multiforme (GBM) - 4. Minimum ADC values were significantly higher in LGG and GBM than ODG. Presurgery, the values were 0.812, 0.633, and 0.787 × 10−3 mm2/s for LGG, ODG, and GBM, respectively. DWI done at the time of RT planning showed values of 0.786, 0.636, 0.869 × 10−3 mm2/s, respectively. During follow-up, the increasing trend of minimum ADC was observed in LGG (P = 0.02). All these patients were clinically and radiologically stable. Anaplastic ODGs, however, showed an initial increase followed by the fall of minimum ADC in all the 5 cases (P = 0.00). Four of the five cases developed progressive disease subsequently. In all the 4 GBM cases, a consistent fall of minimum ADC values was observed (P = 0.00), and they all progressed in spite of RT. Conclusions: The DWI-derived minimum ADC values are an important yet simple quantitative tool to assess the treatment response and disease progression before they are evident on conventional imaging during the follow-up of glial tumors.


Author(s):  
Levent Soydan ◽  
Ali Aslan Demir ◽  
Mehmet Torun ◽  
Makbule Arar Cikrikcioglu

Background: The apparent diffusion coefficient (ADC), the quantitative parameter of diffusion-weighted magnetic resonance imaging (DW-MRI), is a measure for this restricted diffusion, and its role in gastric cancer (GC) including distinguishing malignant segments from healthy gastric wall, metastatic perigastric lymph nodes from benign nodes and evaluating response of GC to neoadjuvant chemotherapy has been investigated in previous studies. Evidence suggests that ADC may also be of help in assessment of aggressiveness and preoperative staging of gastric cancer, which needs to be explored in further studies. Objective: To investigate the role of DW-MRI and its quantitative parameter, ADC in staging of gastric cancer. Methods: Forty-six patients (28 male, 18 female, mean age 62 years) with non-metastatic biopsy-proven GC who underwent abdominal DW-MRI before surgery were included in this retrospective study. Tumor invasion depth (T-stage) and nodal involvement (N-stage) were evaluated using signal increase on DW-MRI, and tumor ADC was measured. Diagnostic performance of these results was assessed by comparing them with postsurgical histopathology based on 8th TNM classification. Results: Sensitivity, specificity, and accuracy of DW-MRI in T-staging were 92.1%, 75%, 89.1% for ≤T2 vs. ≥T3; and 75%, 88.5%, 82.6% for ≤T3 vs. T4. However, sensitivity, specificity, and accuracy of DW-MRI in N-staging were 89.3%, 88.9%, 89.1% for ≤N1 vs. ≥N2; and 73.7%, 96.3%, 86.9% for ≤N2 vs. N3, respectively. Relative preoperative ADC values correlated with pT staging (r=-0.397, p=0.006). There was also a statistically significant difference of relative ADC values between ≤T3 and T4 stages, and a cut-off of 0.64 s/mm2 could differentiate these stages with an odds ratio of 7.714 (95% confidence interval, 1.479-40.243). The area under the receiver operating characteristic curve for differentiating ≤T3 and T4 stages was 0.725. Conclusion: DW-MRI may contribute to the clinical staging of non-metastatic GC. In particular, relative ADC of DW-MRI can distinguish T4 gastric cancer from less advanced T-stages.


2017 ◽  
Vol 38 (10) ◽  
pp. 1769-1780 ◽  
Author(s):  
Benjamin Ménard ◽  
Laurent Chazalviel ◽  
Simon Roussel ◽  
Myriam Bernaudin ◽  
Omar Touzani

Although chronic arterial hypertension (CAH) represents the major comorbid factor in stroke, it is rarely integrated in preclinical studies of stroke. The majority of those investigations employ spontaneously hypertensive rats (SHR) which display a susceptibility to ischemic damage independent of hypertension. Here, we used a renovascular model of hypertension (RH) to examine, with magnetic resonance imaging (MRI), brain alterations during the development of hypertension and after brain ischemia. We also examined whether MRI-derived parameters predict the extent of ischemia-induced brain damage. RH was induced according to the two-kidney one-clip model and multiparametric MRI was performed at 3, 6, 9, and 12 weeks after hypertension and also at 10, 50, and 60 min following stroke. Blood pressure values increased progressively and reached a plateau at 6 weeks after RH induction. At 12 weeks, all hypertensive animals displayed spontaneous brain lesions (hemorrhages, deep and cortical lesions, ventricular dilatation), increased apparent diffusion coefficient (ADC) values in the corpus callosum and higher fractional anisotropy in the cortex. Following ischemia, these animals showed larger brain lesions (406 ± 82 vs. 179 ± 36 mm3, p < 0.002) which correlated with ADC values at chronic stage of hypertension. This model of hypertension displays many characteristics of the neuropathology of human CAH. The use of this model in stroke studies is relevant and desirable.


2018 ◽  
Vol 28 (5) ◽  
pp. 861-868 ◽  
Author(s):  
Ryo Kuwahara ◽  
Aki Kido ◽  
Shiro Tanaka ◽  
Kaoru Abiko ◽  
Kyoko Nakao ◽  
...  

ObjectivesThe aim of this study was to assess the prognostic and incremental value of pretreatment apparent diffusion coefficient (ADC) values of tumors for the prediction of tumor recurrence after complete resection of the tumor in patients with endometrial cancer.MethodsThis study enrolled 210 patients with stages IA to IIIC endometrial cancer who had undergone complete resection of the tumor and pretreatment magnetic resonance imaging. The minimum and mean ADC values (ADCmin, ADCmean) of tumors and normalized ADC (nADCmin, nADCmean) were calculated from magnetic resonance imaging. The primary outcome was recurrence-free survival (RFS). Receiver operating characteristic analysis was performed to compare the diagnostic performance of ADC values of 4 types. The Kaplan-Meier method, log-rank tests, and Cox regression were used to explore associations between recurrence and the ADC values with adjustment for clinicopathological factors.ResultsIn receiver operating characteristic curve analysis, the areas under the curve were significant for ADCmean and nADCmean predicting tumor recurrence but were not significant for ADCmin and nADCmin. Regarding univariate analysis, ADCmean and nADCmean were significantly associated with increased risk of recurrence. Multivariate analysis showed that ADCmean and nADCmean remained independently associated with shorter RFS. In the high-risk group, the RFS of patients with lower ADC values (ADCmean and nADCmean) was significantly shorter than that of patients in the higher ADC value group.ConclusionsPretreatment tumor ADCmean and nADCmean were important imaging biomarkers for predicting recurrence in patients after complete resection of the tumor. They might improve existing risk stratification.


2020 ◽  
Vol 33 (3) ◽  
pp. 201-209
Author(s):  
Theeraphol Panyaping ◽  
Piyakarn Taebunpakul ◽  
Oranan Tritanon

Objective The aim of this study was to differentiate suprasellar germinomas from chiasmatic/hypothalamic gliomas (CHGs) using apparent diffusion coefficient (ADC) values and magnetic resonance imaging (MRI) characteristics. Materials and methods A cross-sectional study was conducted on 11 patients with suprasellar germinomas and 11 patients with CHGs who underwent pretreatment MRI. The ADC values (minimum and average ADC values) of the tumors were measured and the MRI characteristics were evaluated. Results The average and minimum ADC values of suprasellar germinomas were significantly lower than those of CHGs ( p = 0.016 and 0.004 respectively). The selection of 941.15 × 10−6 mm2/s as a cutoff value of the minimum ADC value was used to differentiate suprasellar germinomas and CHGs; the best results were obtained with area under the curve of 0.889, sensitivity of 87.5%, specificity of 77.8% and accuracy of 82.4%. MRI characteristics suggested the diagnosis of suprasellar germinomas were T2W hypointensity and involvement of pituitary gland and/or stalk. MRI characteristics suggested the diagnosis of CHGs was higher degree of contrast enhancement and presence of macrocysts. Conclusion ADC values have a role in differentiating suprasellar germinomas and CHGs, especially when imaging findings on conventional MRI are inconclusive. Furthermore, some MRI features are in favor of differentiation between these tumor entities including tumor location, cyst pattern, T2W hypointensity, degree of contrast enhancement, stalk and pituitary gland involvement.


2001 ◽  
Vol 21 (5) ◽  
pp. 577-584 ◽  
Author(s):  
Jens Fiehler ◽  
René Knab ◽  
Jürgen R. Reichenbach ◽  
Clemens Fitzek ◽  
Cornelius Weiller ◽  
...  

Perfusion-and diffusion-weighted magnetic resonance imaging scans are thought to allow the characterization of tissue at risk of infarction. The authors tested the hypothesis that the apparent diffusion coefficient (ADC) decrease should be associated with the severity of the perfusion deficit in ischemic tissue of acute stroke patients. Perfusion-and diffusion-weighted scans were performed in 11 patients with sudden onset of neurologic deficits within the last 6 hours and T2-weighted magnetic resonance imaging scans were obtained after 6 days. Parameter images of the maximum of the contrast agent concentration, time to peak, relative cerebral blood volume, relative cerebral blood flow, and relative mean transit time were computed from the perfusion-weighted data. A threshold function was used to identify tissue volumes with stepwise ADC decreases. An onionlike distribution of successively decreasing ADC values was found, with the lowest ADC in the center of the ischemic region. Correspondingly, tissue perfusion decreased progressively from the periphery toward the ischemic core. This effect was most pronounced in the time-to-peak maps, with a linear association between ADC decrease and time-to-peak increase. Apparent diffusion coefficient values decreased from the periphery toward the ischemic core, and this distribution of ADC values was strongly associated with the severity of the perfusion deficit.


Author(s):  
Apoorva Muralidhar ◽  
Ashok Kumar ◽  
Arjun Prakash ◽  
Umesh Krishnamurthy ◽  
Manjunath S. ◽  
...  

Abstract Background and Purpose It is estimated that hippocampal damage is seen in 50 to 70% of patients with temporal lobe epilepsy (TLE). Although most magnetic resonance imaging (MRI) studies are adequate to detect gross hippocampal atrophy, subtle changes that may characterize early disease in TLE, such as visually nonappreciable volume loss, may often be missed if objective volumetric analysis is not undertaken. Materials and Methods We conducted a hospital-based prospective analytical study in which 40 patients with partial seizures of temporal lobe origin were included and their hippocampal volumes (HVs) were determined by manual volumetric analysis. The findings were recorded and correlated with the side of seizure and its duration. The quantitative assessment was allotted different grades accordingly. Also, the apparent diffusion coefficient (ADC) values of bilateral hippocampi were estimated and their correlation with the side of seizure was determined. Results Most patients in the study were in the age group of 11 to 20 years (37.5%). In total, 57.5% had seizures for a period of 1 to 5 years. While 67.5% (n = 27) had seizure on the right, 32.5% (n = 13) had on the left. The mean HV estimated on the right and left were correlated with the side of seizure and found to be statistically significant (p < 0.001 in those with right-sided seizures and p = 0.02 in those with left-sided seizures). Simultaneously the ADC values estimated were found to correlate with the laterality of seizures with a statistical difference (p < 0.01). Duration of seizures however did not show a positive correlation with the HV. Conclusion MRI with quantitative estimation of HV and ADC values can depict the presence and laterality in TLE with accuracy rates that exceed those achieved by visual inspection alone. Thus, quantitative MRI provides a useful means for translating volumetric analysis into clinical practice.


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